diff options
Diffstat (limited to 'kernel/trace/trace_selftest.c')
| -rw-r--r-- | kernel/trace/trace_selftest.c | 459 |
1 files changed, 363 insertions, 96 deletions
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 288541f977f..5ef60499dc8 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -21,13 +21,13 @@ static inline int trace_valid_entry(struct trace_entry *entry) return 0; } -static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) +static int trace_test_buffer_cpu(struct trace_buffer *buf, int cpu) { struct ring_buffer_event *event; struct trace_entry *entry; unsigned int loops = 0; - while ((event = ring_buffer_consume(tr->buffer, cpu, NULL, NULL))) { + while ((event = ring_buffer_consume(buf->buffer, cpu, NULL, NULL))) { entry = ring_buffer_event_data(event); /* @@ -58,16 +58,16 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) * Test the trace buffer to see if all the elements * are still sane. */ -static int trace_test_buffer(struct trace_array *tr, unsigned long *count) +static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count) { unsigned long flags, cnt = 0; int cpu, ret = 0; /* Don't allow flipping of max traces now */ local_irq_save(flags); - arch_spin_lock(&ftrace_max_lock); + arch_spin_lock(&buf->tr->max_lock); - cnt = ring_buffer_entries(tr->buffer); + cnt = ring_buffer_entries(buf->buffer); /* * The trace_test_buffer_cpu runs a while loop to consume all data. @@ -78,12 +78,12 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count) */ tracing_off(); for_each_possible_cpu(cpu) { - ret = trace_test_buffer_cpu(tr, cpu); + ret = trace_test_buffer_cpu(buf, cpu); if (ret) break; } tracing_on(); - arch_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&buf->tr->max_lock); local_irq_restore(flags); if (count) @@ -103,54 +103,62 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret) static int trace_selftest_test_probe1_cnt; static void trace_selftest_test_probe1_func(unsigned long ip, - unsigned long pip) + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) { trace_selftest_test_probe1_cnt++; } static int trace_selftest_test_probe2_cnt; static void trace_selftest_test_probe2_func(unsigned long ip, - unsigned long pip) + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) { trace_selftest_test_probe2_cnt++; } static int trace_selftest_test_probe3_cnt; static void trace_selftest_test_probe3_func(unsigned long ip, - unsigned long pip) + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) { trace_selftest_test_probe3_cnt++; } static int trace_selftest_test_global_cnt; static void trace_selftest_test_global_func(unsigned long ip, - unsigned long pip) + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) { trace_selftest_test_global_cnt++; } static int trace_selftest_test_dyn_cnt; static void trace_selftest_test_dyn_func(unsigned long ip, - unsigned long pip) + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) { trace_selftest_test_dyn_cnt++; } static struct ftrace_ops test_probe1 = { .func = trace_selftest_test_probe1_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static struct ftrace_ops test_probe2 = { .func = trace_selftest_test_probe2_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static struct ftrace_ops test_probe3 = { .func = trace_selftest_test_probe3_func, -}; - -static struct ftrace_ops test_global = { - .func = trace_selftest_test_global_func, - .flags = FTRACE_OPS_FL_GLOBAL, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static void print_counts(void) @@ -172,7 +180,7 @@ static void reset_counts(void) trace_selftest_test_dyn_cnt = 0; } -static int trace_selftest_ops(int cnt) +static int trace_selftest_ops(struct trace_array *tr, int cnt) { int save_ftrace_enabled = ftrace_enabled; struct ftrace_ops *dyn_ops; @@ -207,7 +215,11 @@ static int trace_selftest_ops(int cnt) register_ftrace_function(&test_probe1); register_ftrace_function(&test_probe2); register_ftrace_function(&test_probe3); - register_ftrace_function(&test_global); + /* First time we are running with main function */ + if (cnt > 1) { + ftrace_init_array_ops(tr, trace_selftest_test_global_func); + register_ftrace_function(tr->ops); + } DYN_FTRACE_TEST_NAME(); @@ -219,8 +231,10 @@ static int trace_selftest_ops(int cnt) goto out; if (trace_selftest_test_probe3_cnt != 1) goto out; - if (trace_selftest_test_global_cnt == 0) - goto out; + if (cnt > 1) { + if (trace_selftest_test_global_cnt == 0) + goto out; + } DYN_FTRACE_TEST_NAME2(); @@ -256,8 +270,10 @@ static int trace_selftest_ops(int cnt) goto out_free; if (trace_selftest_test_probe3_cnt != 3) goto out_free; - if (trace_selftest_test_global_cnt == 0) - goto out; + if (cnt > 1) { + if (trace_selftest_test_global_cnt == 0) + goto out; + } if (trace_selftest_test_dyn_cnt == 0) goto out_free; @@ -282,7 +298,9 @@ static int trace_selftest_ops(int cnt) unregister_ftrace_function(&test_probe1); unregister_ftrace_function(&test_probe2); unregister_ftrace_function(&test_probe3); - unregister_ftrace_function(&test_global); + if (cnt > 1) + unregister_ftrace_function(tr->ops); + ftrace_reset_array_ops(tr); /* Make sure everything is off */ reset_counts(); @@ -302,12 +320,11 @@ static int trace_selftest_ops(int cnt) } /* Test dynamic code modification and ftrace filters */ -int trace_selftest_startup_dynamic_tracing(struct tracer *trace, - struct trace_array *tr, - int (*func)(void)) +static int trace_selftest_startup_dynamic_tracing(struct tracer *trace, + struct trace_array *tr, + int (*func)(void)) { int save_ftrace_enabled = ftrace_enabled; - int save_tracer_enabled = tracer_enabled; unsigned long count; char *func_name; int ret; @@ -318,7 +335,6 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, /* enable tracing, and record the filter function */ ftrace_enabled = 1; - tracer_enabled = 1; /* passed in by parameter to fool gcc from optimizing */ func(); @@ -344,7 +360,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, msleep(100); /* we should have nothing in the buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); if (ret) goto out; @@ -365,7 +381,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, ftrace_enabled = 0; /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); tracing_start(); /* we should only have one item */ @@ -377,45 +393,277 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, } /* Test the ops with global tracing running */ - ret = trace_selftest_ops(1); + ret = trace_selftest_ops(tr, 1); trace->reset(tr); out: ftrace_enabled = save_ftrace_enabled; - tracer_enabled = save_tracer_enabled; /* Enable tracing on all functions again */ ftrace_set_global_filter(NULL, 0, 1); /* Test the ops with global tracing off */ if (!ret) - ret = trace_selftest_ops(2); + ret = trace_selftest_ops(tr, 2); + + return ret; +} + +static int trace_selftest_recursion_cnt; +static void trace_selftest_test_recursion_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + /* + * This function is registered without the recursion safe flag. + * The ftrace infrastructure should provide the recursion + * protection. If not, this will crash the kernel! + */ + if (trace_selftest_recursion_cnt++ > 10) + return; + DYN_FTRACE_TEST_NAME(); +} + +static void trace_selftest_test_recursion_safe_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + /* + * We said we would provide our own recursion. By calling + * this function again, we should recurse back into this function + * and count again. But this only happens if the arch supports + * all of ftrace features and nothing else is using the function + * tracing utility. + */ + if (trace_selftest_recursion_cnt++) + return; + DYN_FTRACE_TEST_NAME(); +} + +static struct ftrace_ops test_rec_probe = { + .func = trace_selftest_test_recursion_func, +}; + +static struct ftrace_ops test_recsafe_probe = { + .func = trace_selftest_test_recursion_safe_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, +}; + +static int +trace_selftest_function_recursion(void) +{ + int save_ftrace_enabled = ftrace_enabled; + char *func_name; + int len; + int ret; + + /* The previous test PASSED */ + pr_cont("PASSED\n"); + pr_info("Testing ftrace recursion: "); + + + /* enable tracing, and record the filter function */ + ftrace_enabled = 1; + + /* Handle PPC64 '.' name */ + func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + len = strlen(func_name); + + ret = ftrace_set_filter(&test_rec_probe, func_name, len, 1); + if (ret) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_rec_probe); + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_rec_probe); + + ret = -1; + if (trace_selftest_recursion_cnt != 1) { + pr_cont("*callback not called once (%d)* ", + trace_selftest_recursion_cnt); + goto out; + } + + trace_selftest_recursion_cnt = 1; + + pr_cont("PASSED\n"); + pr_info("Testing ftrace recursion safe: "); + + ret = ftrace_set_filter(&test_recsafe_probe, func_name, len, 1); + if (ret) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_recsafe_probe); + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_recsafe_probe); + + ret = -1; + if (trace_selftest_recursion_cnt != 2) { + pr_cont("*callback not called expected 2 times (%d)* ", + trace_selftest_recursion_cnt); + goto out; + } + + ret = 0; +out: + ftrace_enabled = save_ftrace_enabled; return ret; } #else # define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; }) +# define trace_selftest_function_recursion() ({ 0; }) #endif /* CONFIG_DYNAMIC_FTRACE */ +static enum { + TRACE_SELFTEST_REGS_START, + TRACE_SELFTEST_REGS_FOUND, + TRACE_SELFTEST_REGS_NOT_FOUND, +} trace_selftest_regs_stat; + +static void trace_selftest_test_regs_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + if (pt_regs) + trace_selftest_regs_stat = TRACE_SELFTEST_REGS_FOUND; + else + trace_selftest_regs_stat = TRACE_SELFTEST_REGS_NOT_FOUND; +} + +static struct ftrace_ops test_regs_probe = { + .func = trace_selftest_test_regs_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_SAVE_REGS, +}; + +static int +trace_selftest_function_regs(void) +{ + int save_ftrace_enabled = ftrace_enabled; + char *func_name; + int len; + int ret; + int supported = 0; + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS + supported = 1; +#endif + + /* The previous test PASSED */ + pr_cont("PASSED\n"); + pr_info("Testing ftrace regs%s: ", + !supported ? "(no arch support)" : ""); + + /* enable tracing, and record the filter function */ + ftrace_enabled = 1; + + /* Handle PPC64 '.' name */ + func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + len = strlen(func_name); + + ret = ftrace_set_filter(&test_regs_probe, func_name, len, 1); + /* + * If DYNAMIC_FTRACE is not set, then we just trace all functions. + * This test really doesn't care. + */ + if (ret && ret != -ENODEV) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_regs_probe); + /* + * Now if the arch does not support passing regs, then this should + * have failed. + */ + if (!supported) { + if (!ret) { + pr_cont("*registered save-regs without arch support* "); + goto out; + } + test_regs_probe.flags |= FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED; + ret = register_ftrace_function(&test_regs_probe); + } + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_regs_probe); + + ret = -1; + + switch (trace_selftest_regs_stat) { + case TRACE_SELFTEST_REGS_START: + pr_cont("*callback never called* "); + goto out; + + case TRACE_SELFTEST_REGS_FOUND: + if (supported) + break; + pr_cont("*callback received regs without arch support* "); + goto out; + + case TRACE_SELFTEST_REGS_NOT_FOUND: + if (!supported) + break; + pr_cont("*callback received NULL regs* "); + goto out; + } + + ret = 0; +out: + ftrace_enabled = save_ftrace_enabled; + + return ret; +} + /* * Simple verification test of ftrace function tracer. * Enable ftrace, sleep 1/10 second, and then read the trace * buffer to see if all is in order. */ -int +__init int trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) { int save_ftrace_enabled = ftrace_enabled; - int save_tracer_enabled = tracer_enabled; unsigned long count; int ret; +#ifdef CONFIG_DYNAMIC_FTRACE + if (ftrace_filter_param) { + printk(KERN_CONT " ... kernel command line filter set: force PASS ... "); + return 0; + } +#endif + /* make sure msleep has been recorded */ msleep(1); /* start the tracing */ ftrace_enabled = 1; - tracer_enabled = 1; ret = tracer_init(trace, tr); if (ret) { @@ -430,7 +678,7 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) ftrace_enabled = 0; /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -442,10 +690,16 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) ret = trace_selftest_startup_dynamic_tracing(trace, tr, DYN_FTRACE_TEST_NAME); + if (ret) + goto out; + + ret = trace_selftest_function_recursion(); + if (ret) + goto out; + ret = trace_selftest_function_regs(); out: ftrace_enabled = save_ftrace_enabled; - tracer_enabled = save_tracer_enabled; /* kill ftrace totally if we failed */ if (ret) @@ -461,8 +715,6 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) /* Maximum number of functions to trace before diagnosing a hang */ #define GRAPH_MAX_FUNC_TEST 100000000 -static void -__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode); static unsigned int graph_hang_thresh; /* Wrap the real function entry probe to avoid possible hanging */ @@ -472,8 +724,11 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace) if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) { ftrace_graph_stop(); printk(KERN_WARNING "BUG: Function graph tracer hang!\n"); - if (ftrace_dump_on_oops) - __ftrace_dump(false, DUMP_ALL); + if (ftrace_dump_on_oops) { + ftrace_dump(DUMP_ALL); + /* ftrace_dump() disables tracing */ + tracing_on(); + } return 0; } @@ -484,18 +739,25 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace) * Pretty much the same than for the function tracer from which the selftest * has been borrowed. */ -int +__init int trace_selftest_startup_function_graph(struct tracer *trace, struct trace_array *tr) { int ret; unsigned long count; +#ifdef CONFIG_DYNAMIC_FTRACE + if (ftrace_filter_param) { + printk(KERN_CONT " ... kernel command line filter set: force PASS ... "); + return 0; + } +#endif + /* * Simulate the init() callback but we attach a watchdog callback * to detect and recover from possible hangs */ - tracing_reset_online_cpus(tr); + tracing_reset_online_cpus(&tr->trace_buffer); set_graph_array(tr); ret = register_ftrace_graph(&trace_graph_return, &trace_graph_entry_watchdog); @@ -518,7 +780,7 @@ trace_selftest_startup_function_graph(struct tracer *trace, tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -545,7 +807,7 @@ out: int trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -557,7 +819,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable interrupts for a bit */ local_irq_disable(); udelay(100); @@ -573,9 +835,9 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); @@ -584,7 +846,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) ret = -1; } - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -594,7 +856,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) int trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -619,7 +881,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable preemption for a bit */ preempt_disable(); udelay(100); @@ -635,9 +897,9 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); @@ -646,7 +908,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) ret = -1; } - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -656,7 +918,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) int trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -681,7 +943,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable preemption and interrupts for a bit */ preempt_disable(); @@ -701,11 +963,11 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (ret) goto out; - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); if (ret) goto out; @@ -716,7 +978,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * } /* do the test by disabling interrupts first this time */ - tracing_max_latency = 0; + tr->max_latency = 0; tracing_start(); trace->start(tr); @@ -731,11 +993,11 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (ret) goto out; - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); if (!ret && !count) { printk(KERN_CONT ".. no entries found .."); @@ -747,7 +1009,7 @@ out: tracing_start(); out_no_start: trace->reset(tr); - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -765,11 +1027,16 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr) #ifdef CONFIG_SCHED_TRACER static int trace_wakeup_test_thread(void *data) { - /* Make this a RT thread, doesn't need to be too high */ - static const struct sched_param param = { .sched_priority = 5 }; + /* Make this a -deadline thread */ + static const struct sched_attr attr = { + .sched_policy = SCHED_DEADLINE, + .sched_runtime = 100000ULL, + .sched_deadline = 10000000ULL, + .sched_period = 10000000ULL + }; struct completion *x = data; - sched_setscheduler(current, SCHED_FIFO, ¶m); + sched_setattr(current, &attr); /* Make it know we have a new prio */ complete(x); @@ -778,11 +1045,13 @@ static int trace_wakeup_test_thread(void *data) set_current_state(TASK_INTERRUPTIBLE); schedule(); + complete(x); + /* we are awake, now wait to disappear */ while (!kthread_should_stop()) { /* - * This is an RT task, do short sleeps to let - * others run. + * This will likely be the system top priority + * task, do short sleeps to let others run. */ msleep(100); } @@ -793,23 +1062,23 @@ static int trace_wakeup_test_thread(void *data) int trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; struct task_struct *p; - struct completion isrt; + struct completion is_ready; unsigned long count; int ret; - init_completion(&isrt); + init_completion(&is_ready); - /* create a high prio thread */ - p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test"); + /* create a -deadline thread */ + p = kthread_run(trace_wakeup_test_thread, &is_ready, "ftrace-test"); if (IS_ERR(p)) { printk(KERN_CONT "Failed to create ftrace wakeup test thread "); return -1; } - /* make sure the thread is running at an RT prio */ - wait_for_completion(&isrt); + /* make sure the thread is running at -deadline policy */ + wait_for_completion(&is_ready); /* start the tracing */ ret = tracer_init(trace, tr); @@ -819,39 +1088,37 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; - /* sleep to let the RT thread sleep too */ - msleep(100); + while (p->on_rq) { + /* + * Sleep to make sure the -deadline thread is asleep too. + * On virtual machines we can't rely on timings, + * but we want to make sure this test still works. + */ + msleep(100); + } - /* - * Yes this is slightly racy. It is possible that for some - * strange reason that the RT thread we created, did not - * call schedule for 100ms after doing the completion, - * and we do a wakeup on a task that already is awake. - * But that is extremely unlikely, and the worst thing that - * happens in such a case, is that we disable tracing. - * Honestly, if this race does happen something is horrible - * wrong with the system. - */ + init_completion(&is_ready); wake_up_process(p); - /* give a little time to let the thread wake up */ - msleep(100); + /* Wait for the task to wake up */ + wait_for_completion(&is_ready); /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); + printk("ret = %d\n", ret); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); - tracing_max_latency = save_max; + tr->max_latency = save_max; /* kill the thread */ kthread_stop(p); @@ -884,7 +1151,7 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr /* stop the tracing. */ tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -916,7 +1183,7 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); |
